diff --git a/api/v1/swagger/definitions/hold.yaml b/api/v1/swagger/definitions/hold.yaml
index ae2c055a30..85bcd66900 100644
--- a/api/v1/swagger/definitions/hold.yaml
+++ b/api/v1/swagger/definitions/hold.yaml
@@ -64,7 +64,7 @@ properties:
     description: Timestamp for the latest hold update
   item_id:
     type:
-      - string
+      - integer
       - "null"
     description: Internal item identifier
   waiting_date: